reflect: fix reference comment to runtime/map.go
reflect: fix reference comment to runtime/map.go

Change-Id: Icb552dc7106afbf6bd4bd3660d632f174153f834
Reviewed-on: https://go-review.googlesource.com/c/go/+/408914
Reviewed-by: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@golang.org>
Reviewed-by: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@google.com>
TryBot-Result: Gopher Robot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Auto-Submit: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@google.com>
Reviewed-by: Cherry Mui <d62e63aa42ce272d7b6a5055d97e942b33a34679@google.com>
Run-TryBot: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@google.com>

golang/go,nawawi/go,golang/go,nawawi/go,nawawi/go,nawawi/go,golang/go,nawawi/go,golang/go,nawawi/go,nawawi/go,golang/go,nawawi/go,golang/go,golang/go,golang/go